JP2011124827A - Portable terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To report to a user after guaranteeing operations of a function block to be reported when it is determined that there is a doubt of disconnection on an FPC substrate. <P>SOLUTION: A control section 301 proceeds to a step S100 of restarting the whole portable terminal 100 when receiving notification of the disconnection from a disconnection detection section 302. The control section 301 proceeds to a step S101 of checking a disconnection state in restart. The control section 301 determines the disconnection state in the step S101, and if it is a disconnection state A, proceeds to a step S201 of performing initial setting required only for checking an operating state of the function block 304 to be used as a report section. In the case except the disconnection state A, the portable terminal 100 determines that there is no section for reporting that there is a risk of the disconnection, and does not start the portable terminal 100. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a mobile terminal device in which a plurality of housings are connected by a flexible printed circuit board.

In recent years, a foldable portable terminal device in which two housings are connected to each other by a hinge portion, or a slide-type device in which a housing forming a display and a housing forming a keyboard are connected in two layers. Mobile terminal devices are the mainstream. In such a portable terminal device, the function blocks and the control circuit for operating each function block are often arranged over a plurality of cases due to restrictions on the arrangement space in the case. For this reason, it is necessary to transmit various signals between the cases, and the circuit boards arranged in the cases are connected by signal lines on the flexible substrate. In the portable terminal device provided with such signal lines for connecting between the cases, there is a problem that the signal lines are likely to be disconnected at the connecting portion that is movable by the opening / closing operation and the sliding operation.
Also, depending on the disconnected signal line, there is a problem that it becomes unsafe such as overcurrent when operating the functional block. If there is a possibility of disconnection, it is safe to detect it and notify the user This is important from the standpoint of ensuring safety.

  Conventionally, there is known one that detects and notifies that there is a risk of disconnection of a signal line (for example, Patent Document 1). Patent Document 1 detects peeling of a flexible printed circuit board (hereinafter referred to as “FPC board”) or disconnection of internal wiring, and notifies the result by a liquid crystal display device. Specifically, in the FPC board disposed between the liquid crystal panel and the liquid crystal driver board, two detection lines for detecting separation or disconnection are formed separately from the control signal line. In Patent Document 1, the disconnection is detected by logically summing the voltage values of the two detection lines, and warning information is displayed on the liquid crystal panel. As described above, Patent Document 1 detects and notifies the disconnection of the control signal line connecting the liquid crystal panel as the display function block and the liquid crystal driver.

JP 2008-15287 A

However, in Patent Document 1, since the signal line for controlling the display function block and the function block used as the notification means is not arranged on the same FPC board, as realized in the mobile terminal device, When the housing in which the CPU is arranged via the FPC board and the functional block used as the notification means (for example, a display function block) are in different housings, the user tries to inform the user that there is a risk of disconnection. Then, there was a problem that another FPC board had to be installed.
In addition, when there is a possibility that the FPC board is disconnected, a predetermined function block (for example, a display function block or an audio output function block) used as a notification means is not operating in an unsafe state such as an overcurrent. There was a problem that there was no means to judge.

  SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a mobile terminal device capable of notifying using a functional block that is not unsafe while a predetermined functional operation is continued under certain conditions when a disconnection is detected. It is to be.

In order to achieve the above object, a mobile terminal device according to the present invention includes a first housing, a second housing, a connecting portion that connects the first housing and the second housing, A first circuit board provided in the first casing; a second circuit board in which a functional block having a notification function provided in the second casing is disposed; A multilayer flexible board connecting the first circuit board and the second circuit board, the first circuit board detecting a disconnection of a signal line wired to the flexible board, and the function A current measuring unit that measures a current consumed by the block; and a control unit that controls the functional block based on a result measured by the current measuring unit, and the signal line of the functional block is provided on the flexible substrate. Point-symmetrical When the disconnection detection unit detects the disconnection of the signal line of the flexible substrate, the current measurement unit measures the operating current of the functional block. Start up and adopt a configuration to notify that it is disconnected.
With this configuration, when a disconnection on the flexible board connecting between the casings is detected, under certain conditions, a predetermined functional block serving as a notification unit is continuously operated to notify the user of the disconnection. Can be notified.

  According to the present invention, when a disconnection on the flexible substrate is detected by the disconnection detection unit, the degree of disconnection of the functional block signal can be determined. Further, under certain conditions, a predetermined functional block serving as a notification unit can be continuously operated, and can be used as a notification unit. In particular, the above-mentioned certain conditions are unsafe by measuring the operating current of a given functional block when disconnection is detected, and adding the function block operating state determined by the operating current to the function block availability condition. It is possible to prevent the functional block from being used under certain conditions.

1 is a perspective view of an open state of a mobile terminal device according to Embodiment 1 of the present invention. The top view of the open state of the portable terminal device which concerns on Embodiment 1 of this invention The top view of the principal part of the portable terminal device which concerns on Embodiment 1 of this invention. Functional block diagram of the main part of the mobile terminal device according to Embodiment 1 of the present invention The top view of the FPC board which concerns on Embodiment 1 of this invention Sectional drawing of the FPC board which concerns on Embodiment 1 of this invention Sectional drawing which shows arrangement | positioning of the signal wire | line in the FPC board which concerns on Embodiment 1 of this invention Projection diagram showing arrangement of signal lines on FPC board according to Embodiment 1 of the present invention Sectional drawing which shows arrangement | positioning of the signal wire | line in the FPC board which concerns on Embodiment 1 of this invention The figure which showed the threshold value which judges the disconnection state of an FPC board at the time of disconnection detection of the portable terminal device which concerns on Embodiment 1 of this invention The flowchart which shows the process of the portable terminal device at the time of the disconnection detection which concerns on Embodiment 1 of this invention. 1 is a circuit configuration diagram of a current detection unit of a portable terminal device according to Embodiment 1 of the present invention. The flowchart which shows the process at the time of the current measurement of the portable terminal device which concerns on Embodiment 1 of this invention. The figure which showed the threshold value which judges the starting state of a functional block at the time of the current measurement of the portable terminal device which concerns on Embodiment 1 of this invention

  Hereinafter, a specific configuration of the mobile terminal device of the present invention will be described with reference to an embodiment of the present invention. In the following, a foldable mobile phone terminal will be described as an example of a mobile terminal device. However, any mobile terminal device that includes an FPC board that connects between cases as a part of the device configuration may be used. It may be a portable terminal device.

(Embodiment 1)
In Embodiment 1 of the present invention, a foldable mobile phone device will be described. FIG. 1 shows a perspective view of the foldable mobile phone device 100 according to the first embodiment in an opened state. A casing 2 having a main display 5 is connected to a casing 1 having an operation key 4 such as a dial button by a hinge portion 3 (connecting portion) so as to be opened and closed.

  FIG. 2 shows a plan view when the components of the foldable mobile phone device 100 are disassembled. The housing 1 includes an operation key 4, a circuit board 21, and a connector 24. The housing 2 includes a main display 5, a circuit board 22, and a connector 25. Moreover, the hinge part 3 has the FPC board | substrate 23 inside. In some cases, the FPC board 23 and the circuit board 21 or the circuit board 22 are integrally formed. In this case, the connector 24 or the connector 25 may not be provided. If an anisotropic conductive film (ACF) is used for the configuration of the connector section 24 and the connector 25, the connector 24 or the connector 25 may not be provided. Each configuration will be described in detail below.

  The first housing 1 has a substantially box shape, is connected to the second housing 2 via a hinge portion 3, and is rotatable with respect to the hinge portion 3. The first housing 1 has a first circuit board 21 inside. The first housing 1 has an operation key unit operated by the user.

  The second housing 2 has a substantially box shape, is connected to the first housing 1 via a hinge portion 3, and is rotatable with respect to the hinge portion 3. The second housing 2 has a second circuit board 22 inside. The second housing 2 has a main display 5 that displays an operation menu, an image of incoming call information, and the like.

  The hinge part 3 (connecting part) connects the first casing 1 and the second casing 2 so as to be rotatable. Moreover, the hinge part 3 has the FPC board | substrate 23 inside. The description of the arrangement of the signal lines on the FPC board 23 will be described later.

The first circuit board 21 has a connector 24 connected to the FPC board 23. When the first circuit board 21 and the FPC board 23 are integrally formed, the connector 24 is not necessary.
The first circuit board 21 is electrically connected to the second circuit board 22 via the connector 24, the FPC board 23, and the connector 25. When the second circuit board 22 and the FPC board 23 are integrally formed, the connector 25 is not necessary. The circuit configuration of the first circuit board 21 and the circuit configuration of the second circuit board 22 will be described later.

  Next, the structure of the principal part of the portable terminal device 100 is demonstrated in detail using FIG. FIG. 3 is a plan view of a main part of the mobile terminal device 100. In FIG. 3, parts having the same configuration as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.

  The first circuit board 21 controls the entire portable terminal device, and mainly includes a control unit 301 composed mainly of a CPU (central processing unit), a disconnection detection unit 302 having an analog / digital conversion function, and analog / digital. It has a conversion function, a current measuring unit 303 having a monitoring resistance switching unit, and a resistor 401. The signal lines printed on the first circuit board 21 will be described later.

  The second circuit board 22 includes a functional block 304 used for notification means, a resistor 402, and a resistor 403. Here, the functional block used for the notification means is composed of electronic components necessary for operating main display display, speaker ringing, and LED lighting, for example. The signal lines printed on the second circuit board 22 will be described later.

  Next, the configuration of the signal lines in the mobile terminal device 100 will be described in detail with reference to FIG. FIG. 4 is a functional block diagram of a main part of the mobile terminal device 100. 4, parts having the same configuration as in FIG. 3 are denoted by the same reference numerals and description thereof is omitted.

  The first circuit board 21 includes a disconnection detection unit signal line 531 that connects the control unit 301 and the disconnection detection unit 302, a current measurement unit signal line 541 that connects the control unit 301 and the current measurement unit 303, and a control unit. The functional block signal line 501 that connects 301 and the FPC board 23, the first detection signal line 511 that connects the disconnection detector 302 and the FPC board 23, and the FPC board 23 and the first resistor 401 are connected. The second detection signal line 521 is printed.

  The second circuit board 22 includes a function block signal line 504 that connects the FPC board 23 and the function block unit 304 having a notification function, and a third detection signal that connects the FPC board 23 and the second resistor 402. A line 512, a fourth detection signal line 513 connecting the FPC board 23 and the third resistor 403, a signal line 522 connecting the second resistor 402 and the FPC board 23, and a third resistor 403. The signal line 523 connecting the signal line 522 and the fifth detection signal line 524 connecting the signal line 523 and the FPC board 23 are printed. The signal lines printed on the FPC board 23 will be described later.

FIG. 5 shows the configuration of the FPC board 23. The FPC board 23 is formed of a flexible material. In addition, the FPC board 23 includes a joining portion 23a connected to the connector 24, a joining portion 23b connected to the connector 25, and a wiring board portion 23c. The FPC board 23 has a function block signal line 501, a signal line 502 having the same function branched from the function block signal line 501, and a branched signal line 503 having the same function branched from the function block signal 501. A function block signal line 504 connecting the function block signal line 502 and the function block signal line 503, a third detection signal line 512 having the same function and branching from the first detection signal line 511, An insulating portion is provided that insulates the fourth detection signal line 513 having the same function from the first detection signal line 511 and the fifth detection signal line 524 from each other and from the outside. .
FIG. 6 is a cross-sectional view of the FPC board 23 taken along the line aa ′ of FIG. As shown in FIG. 6, the FPC board 23 has a multilayer structure. Specifically, the FPC board 23 has a four-layer structure including a first layer L1, a second layer L2, a third layer L3, and a fourth layer L4. Further, between the upper surface of the first layer L1, between the first layer L1 and the second layer L2, between the second layer L2 and the third layer L3, and between the third layer L3 and the fourth layer L4 And the lower surface of the fourth layer L4 are insulated from each other by an insulating portion. Note that the number of layers of the FPC board 203 is not limited to four, and may be any number of layers.

  Next, the arrangement of the signal lines in the wiring board portion 23c of the FPC board 23 will be described in detail with reference to FIGS. 7-10, the same code | symbol is attached | subjected to the part which is the same structure as FIG. 4, and the description is abbreviate | omitted.

FIG. 7 is a cross-sectional view showing the arrangement of signal lines in the cross-sectional view of the FPC board 23 taken along the line aa ′ of FIG. Specifically, the third detection signal line 513 and the fourth detection signal line 514 are arranged symmetrically with respect to a point 23d at the center in the sectional view. When a break occurs in the wiring board portion 23c of the FPC board 23, either the upper left where the third detection signal line 513 is arranged or the lower right where the fourth detection signal line 514 is arranged Is often disconnected. That is, when there is a possibility of disconnection in the third detection signal line 513, there is little possibility that the fourth detection signal line 514 is disconnected, and conversely, the fourth detection signal line may be disconnected. If there is, there is little possibility that the third detection signal line is disconnected. A method for determining activation of the mobile terminal device 100 when disconnection is detected will be described later.
The function block signal lines 502 and 503 are also arranged symmetrically with respect to the point 23d as in the case of the detection signal line. If there is a possibility that the functional block signal line 502 is disconnected by this arrangement, the possibility that the functional block signal line 503 is disconnected is reduced, and there is a possibility that the functional block signal line 503 may be disconnected. The possibility that the functional block signal line 502 is disconnected is reduced.

  FIG. 8 is a projection view of the arrangement of the fifth detection signal line 524 on the FPC board 23 as viewed from above, and FIG. 9 is a cross-sectional view of the FPC board 23 taken along the line aa ′ of FIG. FIG. 6 is a cross-sectional view showing the arrangement of fifth detection signal lines 524. Specifically, the signal line 524a is arranged from the joint part 23b toward the joint part 23a, is folded at the joint part 23a, and is arranged like the signal line 524b toward the connection part 23b. Further, it is folded at the connection portion 23b and arranged like a signal line 524c toward the connection portion 23a. The fifth detection signal line 524 is disposed on the inner side of the functional block signal line 502 and the functional block signal line 503. With this arrangement, when any part of 524a, 524b, and 524c in the fifth detection signal line 524 is disconnected, the function block signal line 502 or the entire function block signal line 503 may be disconnected. Therefore, it is possible to determine that the mobile terminal device 100 is a serious failure that should not be activated. A method for determining activation of the mobile terminal device 100 when disconnection is detected will be described later.

  Next, the circuit configuration of the current measuring unit 303 will be described in detail with reference to FIG. FIG. 12 is a circuit configuration diagram of the current measuring unit 303. The current measurement unit 303 includes a current measurement IC 303a having an analog / digital conversion function, a first current monitoring resistor 303b, and a second current monitoring resistor 303c having a resistance value larger than that of the first current monitoring resistor 303b. , A first switch 303d and a second switch 303e. Note that switching is not performed in two steps, and if the number of switches and resistors are increased, measurement can be performed in multiple steps. A switch switching method and a current measurement method will be described later.

Above, description of the structure of the portable terminal device 100 is finished.
Next, the relationship between the detection signal line and the disconnection state will be described with reference to FIG.

  The disconnection detection unit 302 supplies a constant current from the constant current source to the first detection signal line 511. The disconnection detection unit 302 monitors the voltage of the first detection signal line 511 and detects a voltage change. At this time, for example, the circuit unit 301 performs analog / digital conversion on the detected voltage value and compares the converted voltage value with a threshold value to detect a voltage change. The unit 301 is notified that one of the detection signal lines has been disconnected. In the configuration of the disconnection detection unit 302, the supply source may be configured to supply a constant voltage from a constant voltage source.

  In a state where the third detection signal line 512, the fourth detection signal line 513, and the fifth detection signal line 524 are not disconnected, the first detection signal detected by the disconnection detection unit 302 is detected. The voltage of the signal line is equal to or higher than the threshold value A (normal operating range) shown in FIG.

  In addition, the voltage of the first detection signal line 511 decreases when the disconnection occurs only in the third detection signal line 512 or when the disconnection occurs only in the fourth detection signal line 513. Thus, the threshold value B is less than or equal to the threshold value A. Accordingly, the disconnection detection unit 302 detects that the first detection signal line 511 is equal to or greater than the threshold value B and less than the threshold value A, thereby changing to the third detection signal line or the fourth detection signal line. Detect that a disconnection has occurred. Such a state where the voltage of the first detection signal line 511 is equal to or higher than the threshold value B and lower than the threshold value A is referred to as a disconnected state A as shown in FIG. In the disconnection state A, the signal line of either the functional block signal line 502 or the functional block signal line 503 is a signal line when operating the functional block because of the arrangement relationship between the detection signal line and the functional block signal line. It is highly possible that the connection is normal.

Similarly, if both the third detection signal line 512 and the fourth detection signal line 513 are disconnected, or if the fifth detection signal line 524 is disconnected, the disconnection occurs. The voltage of the first detection signal line 511 detected by the detection unit 302 decreases and becomes less than the threshold value A. Therefore, the disconnection detection unit 302 detects both the third detection signal line 512 and the fourth detection signal line 513 by detecting that the first detection signal line 511 is less than the threshold A. It is detected that the signal line is broken or that the fifth detection signal line 524 is broken. Such a state where the first detection signal line 511 is less than the threshold A is referred to as a disconnected state B as shown in FIG. In the disconnection state B, there is a possibility that either the entire function block signal line 502 or the entire function block signal line 503 or both of them are disconnected due to the arrangement relationship between the detection signal line and the function block signal line. Therefore, when operating the functional block, it is unlikely that the function block is normally connected as a signal line. By operating the functional block 304, the mobile terminal device 100 may become unsafe. A method for determining activation of the mobile terminal device 100 when the disconnection state as described above is detected will be described later.
Next, an activation procedure when the mobile terminal device 100 detects a disconnection will be described with reference to FIG. 11 as a case where the function block 304 used as a notification unit has a display function using a main display. Note that the function block 304 is not limited to the display function, and may be a notification by a speaker ringing pattern, a notification by an LED lighting pattern, or the like.
FIG. 11 is a flowchart showing processing of the mobile terminal device when disconnection is detected. When receiving a disconnection notification from the disconnection detection unit 302, the control unit 301 proceeds to step S100 to restart the entire mobile terminal device 100. The control unit 301 proceeds to step S101 for confirming the disconnection state at the time of restart. In step S101, the disconnection state is determined. If the disconnection state is A, the process proceeds to step S201 where initial setting is performed only for confirming the operation state of the functional block 304 used as the notification unit. In a case other than the disconnection state A, the mobile terminal device 100 determines that there is no means for notifying that there is a risk of disconnection, and does not activate the mobile terminal device 100.
In step S102, after the initial setting necessary for the operation of the function block 304 is completed, the current during operation is measured, and the process proceeds to step S103 for determining whether the function block can be used from the function operation state. A method for measuring current and a method for determining availability in the functional operation state in step S103 will be described later.
In step S <b> 103, the process proceeds to step S <b> 104 in which the activation mode of the mobile terminal device 100 is determined from the availability determination of the function block 304. In step S104, if the function block can be used as a notification unit as a result of the determination of availability in step S103, the operation state of the function block (not shown) provided on the second circuit board 22 and the second casing 2 is confirmed. The process proceeds to step S105. If the functional block 304 is not usable in step S104, the mobile terminal device 100 determines that there is no means for notifying that there is a risk of disconnection, and does not activate the mobile terminal device 100.
In step S105 for confirming the operation state of functional blocks (not shown) provided on the second circuit board 22 and the second casing 2, for example, a speaker ringing function, an LED lighting function, an IrDA function, etc., are described later. When all the function blocks are determined to be usable according to the method for determining whether or not they can be used in the function operation state, if the unusable function block is activated, the activation is stopped and only the usable function block is activated. Proceed to step S106.
In step S106, it is a step of determining whether or not all function blocks can be used, and starting the mobile terminal device 100 as a function restriction mode, whereby the mobile terminal device 100 functions under an unsafe condition. Can be prevented from continuing to be used, and the function and the reason for the restriction can be notified to the user.

Next, a current measurement method in the current measurement unit 303 and a method for determining availability in the functional operation state will be described with reference to FIGS.
FIG. 13 is a flowchart illustrating processing of the mobile terminal device during current measurement. FIG. 14 is a diagram showing the threshold value of the current during operation and the state of the function block during the function block operation. In the following description, the display function using the main display will be described. The function block is not limited to the display function, and may be a speaker ringing function, an LED lighting function, or the like.

  In the current measuring unit 303 shown in FIG. 12, the switch 303d is normally ON and the switch 303e is OFF. When measuring the current of the functional block, the mobile terminal device 100 proceeds from step S200 shown in FIG. 13 to step S201 for measuring current when the main display is OFF. Subsequently, the process proceeds to step S202 for measuring current when the main display is ON. Further, when the difference between the current measured in step S201 and the current measured in step S202 is used as the operating current of the functional block, the process proceeds to step S203 for determining the appropriateness of the operating current.

  In step S203 for determining the appropriateness of the operating current, the threshold C shown in FIG. 14 is used, and when the operating current is equal to or higher than the threshold C, the use of the display function is not permitted. If it is less than the threshold value C, the threshold value D shown in FIG.

In step S204, when the operating current is equal to or greater than the threshold value D, it is determined that the operating current of the display function is appropriate, and the use of the display function is permitted. In step S204, if the operating current is less than the threshold value D, the current monitoring resistor is changed from the first current monitoring resistor 303b to the second current monitoring resistor 303c in order to enable measurement of a minute current. move on.
In step S205, when the current monitoring resistor is changed from the first current monitoring resistor 303b to the second current monitoring resistor 303c, this is realized by switching the first switch 303d and the second switch 303e. In the state where the first switch 303d is ON, the second switch 303e is turned ON. From the state in which the first switch 303d and the second switch 303e are ON, the current monitoring resistor is changed to the second current monitoring resistor 303c by turning OFF the first switch 303d, and the current when the main display is OFF again. It progresses to step S206 which measures.
In step S206, the current is measured when the main display is OFF. In step S207, the current is measured when the main display is ON. Then, the process proceeds to step S208 for restoring the setting of the switched current monitoring resistor.
In step S208 for returning the setting of the current monitoring resistor, the current monitoring resistor is changed from the second current monitoring resistor 303e to the first current monitoring resistor 303d. At this time, the first switch 303d is turned on, and the second switch 303e is turned off from the state where the first switch 303d and the second switch 303e are turned on. When the switch change is completed, the process proceeds to step S209 for determining the appropriateness of the operating current.
In step S209 for determining whether or not the operating current is appropriate again, if the operating current is equal to or greater than the threshold value D, it is determined that the operating current for the display function is appropriate, and the use of the display function is permitted. When the operating current is less than the threshold value D, the use of the display function is not permitted.

  The present invention is suitable for, for example, a portable terminal device having a foldable casing, and a sliding portable terminal device in which a casing having a display and a casing having a keyboard are stacked in two stages.

DESCRIPTION OF SYMBOLS 100 Folding type mobile telephone apparatus 1 1st housing | casing 2 2nd housing | casing 3 Hinge part 4 Operation key 5 Main display 21 1st circuit board 22 2nd circuit board 23 FPC board 24, 25 Connector 301 Control part 302 Disconnection detection unit 303 Current measurement unit 303a Current measurement IC
303b, 303c Resistor 303d, 303e Switch 304 Function block 401, 402, 403 Resistor

Claims (5)

A first housing, a second housing,
A connecting portion for connecting the first housing and the second housing;
A first circuit board provided in the first housing;
A second circuit board on which functional blocks having a notification function provided in the second housing are arranged;
A multilayer flexible board that passes through the inside of the connecting portion and connects the first circuit board and the second circuit board;
The first circuit board includes a disconnection detection unit that detects a disconnection of a signal line wired to the flexible substrate, a current measurement unit that measures a current consumed by the functional block, and a result measured by the current measurement unit. A control unit for controlling the functional block from
In the flexible substrate, the signal lines of the functional blocks are arranged point-symmetrically in the cross section of the flexible substrate,
When the disconnection detection unit detects the disconnection of the signal line of the flexible substrate, the current measurement unit measures the operating current of the functional block, and activates the functional block if it is within the normal operating range. A portable terminal device that notifies that a disconnection has occurred. In addition to the normal mode in which all functions can be used, the control unit includes a function restriction mode that activates only specific function blocks,
When the disconnection detection unit detects a disconnection of the signal line of the flexible substrate, the current measurement unit measures the operating current of the functional block, and activates only the functional block within the normal operating range. The mobile terminal device according to claim 1, wherein the mobile terminal device notifies that it is in a function restriction mode. The flexible substrate is connected to the first circuit board and the second circuit board, and at least detection signal lines adjacent to the signal lines of the functional block are arranged,
The mobile terminal device according to claim 1, wherein the disconnection detection unit determines that the disconnection is based on a voltage of the detection signal line. When disconnection of the signal line of the flexible substrate is detected by the disconnection detection unit, if the operating current of the functional block is measured by the current measurement unit and is outside the normal operating range, the control is performed. The mobile terminal device according to claim 1, wherein the unit is turned off. The second circuit board includes a first resistor connected to the first detection signal line, a second resistor connected to the first detection signal line, and a second detection signal line. A third resistor connected;
The mobile terminal device according to claim 3, wherein the disconnection position is specified by a change in a combined resistance formed by the first resistor, the second resistor, and the third resistor.

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